Caliper Assessment Vernier Measurement 4 — Questions and Answers
Question 1: On a vernier caliper, the main scale reads 31 mm and the 18th vernier line aligns on a 20-division vernier. What is the measurement?
- 31.90 mm (Correct answer)
- 31.18 mm
- 31.80 mm
- 31.09 mm
Correct answer: 31.90 mm
Least count = 1/20 = 0.05 mm; reading = 31 + (18 × 0.05) = 31 + 0.90 = 31.90 mm.
Question 2: The vernier scale was invented by:
- Pierre Vernier (Correct answer)
- James Watt
- Robert Hooke
- John Wilkinson
Correct answer: Pierre Vernier
Pierre Vernier, a French mathematician, invented the vernier scale in 1631.
Question 3: A step measurement using a vernier caliper involves:
- Measuring the height difference between two surfaces at different levels (Correct answer)
- Measuring the depth of a groove
- Measuring the outer diameter
- Measuring the bore of a cylinder
Correct answer: Measuring the height difference between two surfaces at different levels
Step measurements use the lower jaw tips to find the height difference between two parallel surfaces at different elevations.
Question 4: When vernier caliper jaws show measurable wear at the tips, the instrument should be:
- Sent for recalibration or replaced (Correct answer)
- Used only for internal measurements
- Adjusted by tightening the locking screw
- Compensated by adding a constant to all readings
Correct answer: Sent for recalibration or replaced
Worn jaws reduce accuracy and cannot be reliably corrected in the field; the instrument needs professional recalibration or replacement.
Question 5: Which of the following correctly describes how to read the vernier scale?
- Find the vernier line that most closely aligns with any main scale line (Correct answer)
- Read the first vernier line that passes a main scale line
- Always read the 5th vernier division as a starting point
- Add all vernier division numbers together
Correct answer: Find the vernier line that most closely aligns with any main scale line
The correct technique is to identify the single vernier graduation that aligns exactly (or most closely) with a main scale graduation.
Question 6: A caliper assessment test question shows a vernier with the main scale at 7 cm 3 mm and vernier division 7 aligned on a 10-division scale. What is the reading?
- 73.7 mm
- 7.37 cm (Correct answer)
- 7.07 cm
- 73.07 mm
Correct answer: 7.37 cm
73 mm main scale + (7 × 0.1) mm = 73.7 mm = 7.37 cm (both 73.7 mm and 7.37 cm are correct; 7.37 cm matches option B).
Question 7: Why is a digital caliper generally preferred over a vernier caliper in a fast-paced production environment?
- Digital display eliminates reading errors and speeds up measurement (Correct answer)
- Digital calipers are always more accurate
- Digital calipers do not require zeroing
- Digital calipers measure to 0.001 mm by default
Correct answer: Digital display eliminates reading errors and speeds up measurement
Digital displays reduce the cognitive load of interpreting vernier scales, minimizing human reading errors and increasing throughput.
Caliper Assessment Vernier Measurement 4
On a vernier caliper, the main scale reads 31 mm and the 18th vernier line aligns on a 20-division vernier.
What is the measurement?